Investigating Brain Functional Connectivity and Its Correlation With Cognitive Dysfunction in Chronic Kidney Disease Patients via Resting-State fMRI.

Abstract

Objective: This study aimed to assess the brain functional connectivity and its association with cognitive function in patients with chronic kidney disease (CKD) using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods: A total of 64 CKD patients were enrolled and divided into two groups based on their dependence on dialysis: dialysis-dependent CKD (DD-CKD) group (n = 38) and non-dialysis-dependent CKD (NDD-CKD) group (n = 26). A total of 43 healthy controls (NC) were also recruited and matched for age and sex. Cognitive function was evaluated using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). MRI scans were conducted on a 3.0T Magnetom Skyra scanner equipped with a 32-channel phased array head coil. Data analysis was performed using the Data Processing Assistant for Resting-State fMRI (DPARSF) and Statistical Parametric Mapping (SPM) software.

Results: Cognitive scores (MMSE and MoCA) were significantly lower in both CKD groups compared to healthy controls (p < 0.001), with DD-CKD patients exhibiting worse cognitive performance than NDD-CKD patients (p < 0.05). Laboratory parameters also differed: compared with DD-CKD, NDD-CKD patients had significantly lower levels of protein, creatinine, calcium, and phosphate (all p < 0.05). Network-based statistical analysis revealed reduced functional connectivity in both CKD groups relative to controls (p < 0.05). NDD-CKD patients showed disruptions mainly in the frontal-insular and occipital networks, whereas DD-CKD patients exhibited more extensive alterations involving frontoparietal, cingulate, and visual regions. Correlation analysis further showed that connectivity reductions in key regions-including the dorsolateral prefrontal cortex and parietal association areas-were negatively associated with renal function indicators such as serum creatinine and urea nitrogen (p < 0.05).

Conclusion: Resting-state fMRI effectively reflects alterations in brain functional connectivity in CKD patients and is associated with cognitive performance. Notably, DD-CKD patients showed more extensive network disruptions and more severe cognitive impairment.